The initial automatic transmission to make use of a torque converter (rather than a fluid coupling) was the Buick Dynaflow, which was released for your 1948 product yr. In standard driving, the Dynaflow used only the prime equipment, counting on the torque multiplication in the torque convertor at lower speeds. https://paxtondlqrs.blog-kids.com/34359542/5-simple-statements-about-gearbox-auto-explained